1. Field of Art
This invention relates to recycling scrap materials, and in particular relates to separation of metal and plastic components as in metal closures having plastic liners therein.
2. Brief Description of the Prior Art
Recycling scrap materials is becoming more and more important due to ecology problems caused by discarded scrap and energy and material shortages. Recycling scrap material removes the cause of the objectionable litter and scrap piles, and salvages valuable materials using a fraction of the energy required to produce such materials from their ores or other natural state.
Some scrap materials, such as bottle closures, include joined metal and plastic components which have substantial value for recycling. However, it has heretofore been difficult to separate the metal and plastic components without undue cost which makes recycling impractical. The metal and plastic parts are sometimes bonded together and are not readily separated by conventional means. Scrap which includes both metal and plastic such as polyvinyl chloride should not be remelted because the plastic will produce noxious gas such as chlorine.
Heretofore, separation of plastic and metal components has usually required grinding of the components. When the components are ground, metal fines are produced which cling to the plastic to contaminate the plastic and make it difficult if not impossible to reuse the plastic.
Accordingly, an improved technique is desired for separating metal and plastic components from recyclable material such as metal closures with plastic liners therein.